--- a/OrthancServer/Plugins/Include/orthanc/OrthancCPlugin.h	Thu Sep 30 17:52:07 2021 +0200
+++ b/OrthancServer/Plugins/Include/orthanc/OrthancCPlugin.h	Fri Oct 01 18:36:45 2021 +0200
@@ -461,7 +461,8 @@
     _OrthancPluginService_RegisterIncomingDicomInstanceFilter = 1014,
     _OrthancPluginService_RegisterTranscoderCallback = 1015,   /* New in Orthanc 1.7.0 */
     _OrthancPluginService_RegisterStorageArea2 = 1016,         /* New in Orthanc 1.9.0 */
-    
+    _OrthancPluginService_RegisterIncomingCStoreInstanceFilter = 1017,  /* New in Orthanc 1.9.8 */
+
     /* Sending answers to REST calls */
     _OrthancPluginService_AnswerBuffer = 2000,
     _OrthancPluginService_CompressAndAnswerPngImage = 2001,  /* Unused as of Orthanc 0.9.4 */
@@ -7764,6 +7765,63 @@
 
 
   /**
+   * @brief Callback to filter incoming DICOM instances received by 
+   * Orthanc through C-Store.
+   *
+   * Signature of a callback function that is triggered whenever
+   * Orthanc receives a new DICOM instance (through DICOM protocol), 
+   * and that answers whether this DICOM instance should be accepted 
+   * or discarded by Orthanc.  If the instance is discarded, the callback
+   * can specify the C-Store error code.
+   *
+   * Note that the metadata information is not available
+   * (i.e. GetInstanceMetadata() should not be used on "instance").
+   *
+   * @param instance The received DICOM instance.
+   * @return 0 to accept the instance, any valid C-Store error code
+   * to reject the instance, -1 if error.
+   * @ingroup Callback
+   **/
+  typedef int32_t (*OrthancPluginIncomingCStoreInstanceFilter) (
+    const OrthancPluginDicomInstance* instance);
+
+
+  typedef struct
+  {
+    OrthancPluginIncomingCStoreInstanceFilter callback;
+  } _OrthancPluginIncomingCStoreInstanceFilter;
+
+  /**
+   * @brief Register a callback to filter incoming DICOM instances
+   * received by Orthanc through C-Store.
+   *
+   *
+   * @warning Your callback function will be called synchronously with
+   * the core of Orthanc. This implies that deadlocks might emerge if
+   * you call other core primitives of Orthanc in your callback (such
+   * deadlocks are particular visible in the presence of other plugins
+   * or Lua scripts). It is thus strongly advised to avoid any call to
+   * the REST API of Orthanc in the callback. If you have to call
+   * other primitives of Orthanc, you should make these calls in a
+   * separate thread, passing the pending events to be processed
+   * through a message queue.
+   * 
+   * @param context The Orthanc plugin context, as received by OrthancPluginInitialize().
+   * @param callback The callback.
+   * @return 0 if success, other value if error.
+   * @ingroup Callbacks
+   **/
+  ORTHANC_PLUGIN_INLINE OrthancPluginErrorCode OrthancPluginRegisterIncomingCStoreInstanceFilter(
+    OrthancPluginContext*                     context,
+    OrthancPluginIncomingCStoreInstanceFilter  callback)
+  {
+    _OrthancPluginIncomingCStoreInstanceFilter params;
+    params.callback = callback;
+
+    return context->InvokeService(context, _OrthancPluginService_RegisterIncomingCStoreInstanceFilter, &params);
+  }
+
+  /**
    * @brief Get the transfer syntax of a DICOM file.
    *
    * This function returns a pointer to a newly created string that